ERROR: (device loop0): dbUpdatePMap: blocks are outside the map
blkno = 6161616161, nblocks = 616161
ERROR: (device loop0): dbUpdatePMap: blocks are outside the map
blkno = 6c00003065, nblocks = 69662f
ERROR: (device loop0): dbUpdatePMap: blocks are outside the map
==================================================================
BUG: KASAN: use-after-free in txAllocPMap+0x47f/0x6b0 fs/jfs/jfs_txnmgr.c:2412
Read of size 1 at addr ffff88802f61c000 by task jfsCommit/111

CPU: 1 PID: 111 Comm: jfsCommit Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:364 [inline]
 print_report+0xa8/0x210 mm/kasan/report.c:468
 kasan_report+0x117/0x150 mm/kasan/report.c:581
 txAllocPMap+0x47f/0x6b0 fs/jfs/jfs_txnmgr.c:2412
 txUpdateMap+0x2b7/0x8b0 fs/jfs/jfs_txnmgr.c:2309
 txLazyCommit fs/jfs/jfs_txnmgr.c:2665 [inline]
 jfs_lazycommit+0x439/0xaa0 fs/jfs/jfs_txnmgr.c:2733
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>

The buggy address belongs to the physical page:
page:ffffea0000bd8700 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2f61c
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffff7f(buddy)
raw: 00fff00000000000 ffffea0001dd5788 ffffea0001d44b88 0000000000000000
raw: 0000000000000000 0000000000000001 00000000ffffff7f 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x540dc0(GFP_USER|__GFP_COMP|__GFP_ZERO|__GFP_ACCOUNT), pid 5911, tgid 5911 (sed), ts 87798904584, free_ts 87818794900
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1582
 prep_new_page mm/page_alloc.c:1589 [inline]
 get_page_from_freelist+0x2181/0x22a0 mm/page_alloc.c:3221
 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4501
 pagetable_alloc include/linux/mm.h:2900 [inline]
 __pte_alloc_one include/asm-generic/pgalloc.h:68 [inline]
 pte_alloc_one+0x84/0x540 arch/x86/mm/pgtable.c:33
 __do_fault+0xd7/0x4d0 mm/memory.c:4239
 do_cow_fault mm/memory.c:4674 [inline]
 do_fault mm/memory.c:4777 [inline]
 do_pte_missing mm/memory.c:3689 [inline]
 handle_pte_fault mm/memory.c:5047 [inline]
 __handle_mm_fault mm/memory.c:5188 [inline]
 handle_mm_fault+0x2c86/0x4a50 mm/memory.c:5353
 do_user_addr_fault+0x736/0x12d0 arch/x86/mm/fault.c:1371
 handle_page_fault arch/x86/mm/fault.c:1463 [inline]
 exc_page_fault+0x64/0x100 arch/x86/mm/fault.c:1516
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:608
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1182 [inline]
 free_unref_page_prepare+0x7d7/0x8f0 mm/page_alloc.c:2366
 free_unref_page_list+0xbe/0x860 mm/page_alloc.c:2505
 release_pages+0x208a/0x2300 mm/swap.c:1022
 tlb_batch_pages_flush mm/mmu_gather.c:99 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:294 [inline]
 tlb_flush_mmu+0x379/0x510 mm/mmu_gather.c:301
 tlb_finish_mmu+0xf4/0x220 mm/mmu_gather.c:425
 exit_mmap+0x428/0xb90 mm/mmap.c:3315
 __mmput+0x118/0x3a0 kernel/fork.c:1357
 exit_mm+0x23f/0x340 kernel/exit.c:570
 do_exit+0x909/0x2530 kernel/exit.c:871
 do_group_exit+0x22d/0x2f0 kernel/exit.c:1026
 __do_sys_exit_group kernel/exit.c:1037 [inline]
 __se_sys_exit_group kernel/exit.c:1035 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1035
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Memory state around the buggy address:
 ffff88802f61bf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88802f61bf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88802f61c000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff88802f61c080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88802f61c100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================